Multicolour, multilayer photographic elements are well known in the art. Such materials generally have three different selectively sensitized colour records having one or more silver halide emulsion layers coated on one side of a single support. Each colour record has components useful for forming a particular colour in an image. Typically, the materials utilize colour forming couplers or dyes in the sensitized layers during processing.
One commercially important type of colour photographic elements are what are known as colour prints. These elements are used to display images captured by a camera user on photographic colour negative films. There is continuing interest in the industry to provide colour print images more rapidly so the customers have a shorter wait from the time the colour negative films are submitted for processing to the time they receive the colour prints.
In colour paper processing, the conventional order of the light sensitive colour records on a support is a blue-sensitive silver halide emulsion layer nearest the support, a green-sensitive silver halide emulsion layer next to it, and a red-sensitive silver halide emulsion layer as the topmost light sensitive layer.
The basic image-forming process of colour photography comprises the exposure of a silver halide photographic recording material, such as a paper, to light, and the chemical processing of the material to reveal a useful image. For example, colour negative papers may be exposed by digital means e.g. LED (light emitting diode), laser or CRT (cathode ray tube) in a minilab. The chemical processing involves two fundamental steps. The first is a treatment of the exposed silver halide with a colour developing agent wherein some or all of the silver ion is reduced to metallic silver.
The second is the removal of the silver metal by the individual or combined steps of bleaching and fixing so that only dye remains in the processed material. During bleaching, the developed silver is oxidized to a silver salt by a suitable bleaching agent. During fixing, the oxidized silver is dissolved and removed from the element by a suitable fixing agent.
U.S. Pat. No. 4,962,014 describes a method of processing an exposed colour photographic material comprising the steps of colour developing, bleach-fixing and washing. The bleach-fix solution contains sulphite ion in an amount from 0.08 to 0.30 mol/l. The bleaching agent may be ferric ion complexed with an organic ligand such as ethylenediaminetetraacetic acid (EDTA). The pH of the bleach-fix may be from 4 to 8. The bleaching time is from 30 to 70 seconds.